Built 1697. Roadbed prepared for turnpike 1803. Iron tie bars installed above center arch on both up&downstream sides by 1860. Bridge widened on downstream side 1893. Stone parapets on both sides removed and replaced with overhanging steel and concrete sidewalks and steel railings 1950. 12″ thick concrete layer applied to underside of arches on upstream side about 1950.
“FD Grip” The No.1 earthquake-resistant rebar coupler in Japan, the highest seismic country, for over 30 years.